Methods of deoxygenation and systems for fuel production

ABSTRACT

Presented are one or more aspects and/or one or more embodiments of catalysts, methods of preparation of catalyst, methods of deoxygenation, and methods of fuel production.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims benefit of U.S. Patent Application Ser.No. 61/424,043, Docket No. ETI-003, titled “CATALYSTS, METHODS OFPREPARATION OF CATALYST, METHODS OF DEOXYGENATION, AND METHODS OF FUELPRODUCTION,” to Thien Duyen Thi NGUYEN and Krishniah PARIMI, filed Dec.16, 2010. The present application is related to: PCT Patent ApplicationDocket No. ETI-004PCT, titled “CATALYSTS, METHODS OF PREPARATION OFCATALYST, METHODS OF DEOXYGENATION, AND METHODS FOR FUEL PRODUCTION,” toThien Duyen Thi NGUYEN and Krishniah PARIMI, filed Dec. 16, 2011; U.S.patent application Docket No. ETI-004US1, titled “CATALYSTS AND METHODSOF PREPARATION OF CATALYST,” to Thien Duyen Thi NGUYEN and KrishniahPARIMI, filed Dec. 16, 2011. The contents of all of these applicationsand/or patents are incorporated herein in their entirety by thisreference for all purposes.

BACKGROUND

Catalysts are extensively used in a variety of industrial processes.Because of the diversity of the types of processes, there are many typesof catalysts. The present inventors have made one or more discoveriespertaining to catalysts, methods of making catalysts, and methods ofusing catalysts.

An example of one of the areas in which these discoveries may beapplicable is the use of renewable feedstocks for producingtransportation fuels such as for green energy technologies that seek touse bio-oils to replace petroleum feedstock for fuels. Bio-oils areadvantageous raw fuel feedstocks because they are easy to obtain andtherefore enable fuel cost stabilization and provide energy autonomy.Bio-oils are a renewable resource with significant environmentalbenefits. First, nitrogen and sulfur organic compounds occur much lessin bio-oil feedstocks as compared to petroleum fuels, so less harmfulNO_(x) & SO_(x) emissions will be produced when biofuels are used.Second, CO₂ emissions during the use of biofuels is offset by the plantswhich need the CO₂ to grow, hence it is commonly referred to as carbonneutral.

There is a need for improved catalysts, improved methods of preparingcatalysts, methods of deoxygenation, and/or processes for applicationssuch as, but not limited to, the production of fuel from renewablefeedstocks.

SUMMARY

One or more aspects of this invention pertains to catalysts. One aspectof the invention is a catalyst. According to one embodiment, thecatalyst comprises a porous substrate and an electrolessly depositedcatalytically effective metal coating having a nanoscale thickness.

Another aspect of the invention is a method of making a catalyst.According to one embodiment, the method comprises providing a poroussubstrate, providing a solution that comprises a metal for electrolessdeposition (ELD), mixing the substrate with the solution, controllingthe temperature of the mixture of the substrate and the solution, andramping the temperature while adding a reducing agent incrementally orcontinuously so as to cause controlled electroless deposition of themetal as a catalytically active stable nanoscale coating of thesubstrate.

Another aspect of the invention is a method of deoxygenation. Accordingto one embodiment for deoxygenating oxygenated hydrocarbons, the methodcomprises providing a catalyst comprising a porous substrate and anelectrolessly deposited catalytically effective nanoscale metal coatingon the substrate and contacting the catalyst with the oxygenatedhydrocarbons and hydrogen so as to accomplish hydrogenation anddeoxygenation wherein the deoxygenation is accomplished preferentiallyby decarbonylation and decarboxylation over hydrodeoxygenation.

Another aspect of the invention is a system for producing fuel fromfeedstocks such as bio-oil. According to one embodiment, the systemcomprises a deoxygenation stage, the deoxygenation stage comprises atleast one deoxygenation reactor chamber and a catalyst, and the catalystcomprises a porous substrate and an electrolessly deposited metalcoating having a nanoscale thickness. The system further comprises ahydrocracking and isomerization stage comprising at least onehydrocracking and isomerization reactor and a hydrocracking andisomerization catalyst. The hydrocracking and isomerization stage isconfigured to receive the liquid hydrocarbons from the deoxygenationstage and hydrogen. The hydrocracking and isomerization stage operatesat conditions to convert the liquid hydrocarbons from the deoxygenationstage into gasoline, diesel fuel, and/or aviation/jet fuel.

It is to be understood that the invention is not limited in itsapplication to the details of construction and to the arrangements ofthe components set forth in the following description. The invention iscapable of other embodiments and of being practiced and carried out invarious ways. In addition, it is to be understood that the phraseologyand terminology employed herein are for the purpose of description andshould not be regarded as limiting.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a magnified image of a catalyst according to one embodiment ofthe present invention.

FIG. 1-1 is a typical Arrhenius plot for one or more embodiments of thepresent invention.

FIG. 1-2 is a graph showing Camelina oil composition.

FIG. 1-3 is gas chromatographic data of deoxygenated liquid productaccording to one or more embodiments of the present invention.

FIG. 2 is a flow diagram according to one or more embodiments of thepresent invention.

FIG. 3 is a flow diagram for an example according to one or moreembodiments of the present invention.

FIG. 4 is a flow diagram according to one or more embodiments of thepresent invention.

FIG. 5 is a flow diagram according to one or more embodiments of thepresent invention.

Skilled artisans appreciate that elements in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the elements in the figures maybe exaggerated relative to other elements to help to improveunderstanding of embodiments of the present invention.

DESCRIPTION

For the following defined terms, these definitions shall be applied,unless a different definition is given in the claims or elsewhere inthis specification. All numeric values are herein defined as beingmodified by the term “about,” whether or not explicitly indicated. Theterm “about” generally refers to a range of numbers that a person ofordinary skill in the art would consider equivalent to the stated valueto produce substantially the same properties, function, result, etc. Anumerical range indicated by a low value and a high value is defined toinclude all numbers subsumed within the numerical range and allsubranges subsumed within the numerical range. As an example, the range10 to 15 includes, but is not limited to, 10, 10.1, 10.47, 11, 11.75 to12.2, 12.5, 13 to 13.8, 14, 14.025, and 15. The term “nanoscale” isdefined as having at least one dimension less than 100 nanometers. Theterm “porous substrate” is defined as a pore structure that results inan equivalent surface area for the porous substrate in the range of50-1500 square meters per gram (m²/g) of the porous substrate asmeasured by a technique such as the Brunauer Emmett Teller (BET)technique or an analogous technique. In other words, the porosity of thesubstrate is specified by the equivalent surface area for the poroussubstrate.

Information about the fundamentals of electroless deposition isavailable in the scientific and patent literature. The followingdocuments are incorporated herein in their entirety, for all purposes,by this reference: M. Paunovic and M. Schlesinger “Fundamentals ofElectrochemical Deposition,” Second Edition, John Wiley & SonsIncorporated, Pennington, N.J., 2006; and U.S. Pat. No. 7,514,353.

One aspect of the present invention encompasses a catalyst. Anotheraspect of the invention encompasses methods of making catalysts. Anotheraspect of the invention encompasses methods of using catalysts forapplications such as, but not limited to, deoxygenation of compounds.Another aspect of the invention encompasses methods of makingcarbon-based fuels such as, but not limited to, jet fuel, gasoline, anddiesel fuel using feedstocks derived from sources such as, but notlimited to, plants and other renewable sources.

Catalysts

One aspect of the present invention is a catalyst such as for promotingone or more chemical reactions. Catalysts according to one or moreembodiments of the present invention comprise a porous substrate and oneor more metals dispersed on and/or within the substrate includingsurfaces forming the pores of the substrate. The metal is or can be madeto be catalytically active. According to one embodiment of the presentinvention, the metal is an electrolessly deposited catalyticallyeffective metal coating having a nanoscale thickness. This means thatfor one or more embodiments of the present invention, the metal isdeposited electrochemically by electroless deposition.

According to one embodiment of the present invention, the poroussubstrate has a surface area equivalent of 50-1500 m²/g. According toone or more other embodiments of the present invention, the poroussubstrate has a surface area equivalent in the range of 50-100 m²/g.According to one or more other embodiments of the present invention, theporous substrate has a surface area equivalent in the range of 100-300m²/g. According to one or more other embodiments of the presentinvention, the porous substrate has a surface area equivalent in therange of 300-900 m²/g. According to one or more other embodiments of thepresent invention, the porous substrate has a surface area equivalent inthe range of 900-1500 m²/g.

A variety of substrates can be used for one or more embodiments of thepresent invention. Examples of suitable substrates for embodiments ofthe present invention include, but are not limited to, activated carbon,carbon foam, alumina, metal foam, silica-alumina, silica, zeolites,titania, zirconia, magnesia, chromia, monoliths, or combinationsthereof. Optionally, substrates for one or more embodiments of thepresent invention may be granular or pelletized.

According to one or more embodiments of the present invention, thesubstrates have low levels of impurities that could interfere with theactivity of the catalysts. For example, activated carbon substratespreferably have low metal content and low ash content for someembodiments of the present invention. The impurity levels of someactivated carbon can be reduced by an acid wash of the substrate priorto preparation of the catalyst.

According to one or more embodiments of the present invention, thesubstrate has pores 0.2 nm to 10 nm wide. According to anotherembodiment of the present invention, the substrate has pores 0.2 nm to10 nm wide and the catalytic metal is present in the pores.

The catalyst is substantially stable during the preparation processes,during the activation processes if applicable, and during extendedperiods of use as a catalyst. For one or more embodiments of the presentinvention, the substrates are porous.

According to one or more embodiments of the present invention, thecatalyst comprises one or more metals such as, but not limited to,palladium (Pd), nickel (Ni), chromium (Cr), molybdenum (Mo), tungsten(W), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh),iridium (Ir), platinum (Pt), zinc (Zn), silver (Ag), copper (Cu), gold(Au), or mixtures thereof. Optionally, the catalyst may be configured asa single metal catalyst, as a bi-metallic catalyst, or as a tri-metalliccatalyst. For embodiments of the present invention that have two or moremetals, optionally the metals may be mixed so that they form an alloysuch as palladium and nickel in an alloy. Alternatively, the elementsmay be present as substantially pure elements.

According to one embodiment of the present invention, the metalcomprises palladium formed as nanoscale palladium deposited on thesubstrate surfaces including, but not limited to, the surfaces of pores.Metals other than palladium may be used in the catalytic materials forone or more embodiments of the present invention. Substrates for one ormore embodiments of the present invention include activated carbon suchas coconut activated carbon.

According to one or more embodiments of the present invention, the metalis electrolessly deposited using electroless deposition processes sothat the metal is substantially free of electroless depositionimpurities. In one or more embodiments of the present invention, metaldeposition is electroless deposition accomplished with reducing agentssuch as, but not limited to, hydrazine, aldehydes, carboxylic acids withup to 6 carbon atoms, or mixtures thereof. According to one embodimentof the present invention, the metal deposition is accomplished withhydrazine incrementally or continuously added during the deposition sothat the reducing agent input is distributed.

According to one embodiment of the present invention, the loading of themetal is less than 15% by weight. According to another embodiment of thepresent invention, the loading of the metal is less than 5% by weight.According to yet another embodiment of the present invention, theloading of the metal is less than 1% by weight.

According to one or more embodiments of the present invention, thecatalyst is catalytically active for deoxygenation of molecules such asoxygenated hydrocarbons. An exceptional and unexpected property ofcatalysts according to one or more embodiments of the present inventionis that one or more of the catalysts are catalytically active forpreferential deoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation. Preferential deoxygenation by decarbonylation anddecarboxylation over hydrodeoxygenation is defined as greater than orequal to 60% of oxygen is removed from oxygenated hydrocarbon as carbondioxide and carbon monoxide and less than or equal to 40% of the oxygenis removed as water at all levels of deoxygenation.

According to another embodiment of the present invention, the catalystis catalytically active so as to be capable of preferentialdeoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation of alcohols, ethers, aldehydes, ketones, carboxylicacids, phenolics, esters, or mixtures thereof by decarbonylation anddecarboxylation over hydrodeoxygenation. Catalysts according to one ormore embodiments of the present invention are capable of hydrogenationand preferential deoxygenation of triglycerides by decarbonylation anddecarboxylation over hydrodeoxygenation.

According to another embodiment of the present invention, the metalcomprises palladium, the substrate has pores 0.2 nm to 10 nm wide withthe metal present therein, and the catalyst is active for deoxygenationof triglycerides. According to another embodiment of the presentinvention, the catalyst is catalytically active for hydrogenation andpreferential deoxygenation of triglycerides by decarbonylation anddecarboxylation over hydrodeoxygenation so that the ratio of odd carbonnumber molecules to even carbon number molecules in the deoxygenatedproduct is about 6:1. This ratio is typically less than one for otherdeoxygenation technologies.

Another embodiment of the present invention is a catalyst fordeoxygenating bio-oils for fuel production. The catalyst comprises asubstrate comprising activated carbon in granular form with size in therange of 0.5 mm to 3 mm. The substrate has pores 0.2 nm to 10 nm wide.The catalyst comprises an electrolessly deposited catalyticallyeffective palladium or nickel coating having nanoscale thicknessdisposed on the surfaces of the pores. The palladium or nickel loadingfor the catalyst is less than about 2% by weight. Optionally, the metalcomprises palladium grains about 15 nanometers wide.

One or more embodiments of the present invention comprises a catalystproduced by one or more of the catalyst synthesis processes provided inthe present disclosure. More specifically, one or more embodiments ofthe present invention encompass a product by process. One or moremethods of preparing catalysts, according to embodiments of the presentinvention, produces catalysts having unique properties such as, but notlimited to, morphology, particle size, particle distribution, andchemical reactivity.

Catalysts according to one or more embodiments of the present inventioncan be made using the exemplary processes presented below. Catalystsaccording to one or more embodiments of the present invention are madeusing electroless deposition processes that include one or more stepssuch as, but not limited to, improving bath stabilization, distributingthe introduction of reducing agent, and ramping the temperature of theplating bath. According to one or more embodiments of the presentinvention, the distributed introduction of the reducing agent is coupledwith the ramping of the temperature. One or more embodiments of thepresent invention are the first instance of electroless deposition ofnanoscale palladium coatings on activated carbon. The catalyst is stableand effective for reactions such as deoxygenation.

Prior to one or more embodiments of the present invention, the presentinventors are not aware of electroless plating of palladium as havingbeen demonstrated on granular carbon substrates or other high porositysubstrates. Using electroless deposition according to one or moreembodiments of the present invention, deoxygenation catalyst is producedwith suitable palladium particle size and distribution in the porestructure of the substrate to enable effective deoxygenation of bio-oilsat even very low metal loading. These results are exceptional andunexpected.

Catalysts produced according to one or more embodiments of the presentinvention have suitable palladium distribution within the pore structureof the substrate to enable high catalytic activities under low metalloading. Deposition of palladium on a substrate according to one or moreembodiments of the present invention may be achievable in shorter timeas compared to conventional deposition methods such as incipient wetnessimpregnation.

Reference is now made to FIG. 1 where there is shown a magnified imageof a catalyst according to one embodiment of the present invention. Thesurface is magnified 100,000×. The catalyst comprises a substrate ofactivated carbon and a coating of electrolessly deposited palladiumusing an exemplary process presented below. A group of the particles wasvacuum encapsulated in epoxy and then sectioned using standardmetallographic materials and procedures. The resulting sectionedspecimens were then examined, first by conventional scanning electronmicroscopy (SEM). The first examination suggested that there had beenextensive penetration into and deposition of palladium. The secondexamination Field Emission SEM showed that almost all interior surfaceswere coated with palladium. Palladium was present in islands thatsometimes coalesce, but are often still discontinuous. The islands varygreatly in size, but appear to consist of grains about 15 nm across. Theislands were also present on the deep interior surface of the particles.

Catalysts according to one or more embodiments of the present inventionwere tested. The catalyst had from 0.5% to 5% palladium loading. Thecatalyst showed very little effect of catalytic metal loading ondeoxygenation activity (see Table 1). As shown in FIG. 1-1, the catalystwas found to be very active for deoxygenation activity with activationenergy of about 54 kcal/g-mole for deoxygenation of Camelina oil. Theactivation energy is typical of active zeolite based hydrocrackingcatalysts.

For one or more embodiments of the present invention, the specificsubstrate-active metal combination appears to promote decarbonylation ofplant oils in preference to hydrodeoxygenation in removing oxygen fromthe oil molecule. This is highly advantageous in process design forapplications such as converting plant oils to biofuels and is anexceptional and unexpected result.

When oxygen is removed as oxides of carbon, the product molecule willhave one less carbon. For example, C18 molecule will become C17.Camelina oil, as shown in FIG. 1-2, has C16, C18, C20, C22, and C24molecules, all even numbered. FIG. 1-3 is a gas chromatograph (GC) traceshowing the composition of deoxygenated product produced according toone or more embodiments of the present invention. As the gaschromatograph shows, odd number carbon atoms dominate to the extent theratio of odd and even number atoms is about 6 to 1. In contrast to theresults obtained using embodiments of the present invention, datareported for other processes show that the ratio of odd to even numbercarbon species is in the range from 0 to 1.

Method of Making Catalysts

Another aspect of the invention is a method of making a catalyst.Reference is now made to FIG. 2 where there is shown a flowchart forsynthesis of catalysts according to one or more embodiments of thepresent invention. According to one embodiment, the method comprises 12providing a porous substrate and 14 providing a solution that comprisesa metal for electroless deposition. The method further comprises 16mixing the substrate with the solution and 18 controlling thetemperature of the mixture of the substrate and the solution. Also, themethod comprises 20 ramping up the temperature of the mixture whileadding a reducing agent incrementally or continuously so as to causecontrolled electroless deposition of the metal as a catalytically activenanoscale coating of the substrate. The controlled deposition includescontrol of the rate of deposition of the metal and control of thelocation of the deposited metal. According to one or more embodiments ofthe present invention, the deposition rate is controlled by thedistributed addition of the reducing agent in combination with thecontrolled ramping up of the temperature so as to allow the rate of masstransfer to allow more thorough distribution of the metal through theporous substrate for the metal deposition. According to one or moreembodiments of the present invention, the reducing agent is addedcontinuously or incrementally during most or all of the duration of theelectroless deposition of the metal.

According to one embodiment of the present invention, the methodincludes using a porous substrate having a surface area equivalent of50-1500 m²/g. According to one or more other embodiments of the presentinvention, the porous substrate has a surface area equivalent in therange of 50-100 m²/g. According to one or more other embodiments of thepresent invention, the porous substrate has a surface area equivalent inthe range of 100-300 m²/g. According to one or more other embodiments ofthe present invention, the porous substrate has a surface areaequivalent in the range of 300-900 m²/g. According to one or more otherembodiments of the present invention, the porous substrate has a surfacearea equivalent in the range of 900-1500 m²/g.

A variety of substrates can be used for methods of making catalystsaccording to one or more embodiments of the present invention. Examplesof suitable substrates for embodiments of the present invention include,but are not limited to, activated carbon, carbon foam, alumina, metalfoam, silica, silica-alumina, zeolites, titania, zirconia, magnesia,chromia, monoliths, or combinations thereof. Optionally, substrates forone or more embodiments of the present invention may be granular orpelletized.

According to one or more embodiments of the present invention, themethod includes using a substrate having pores 0.2 nm to 10 nm wide.According to another embodiment of the present invention, the methodincludes depositing metal into substrate pores 0.2 nm to 10 nm wide.

According to one or more embodiments of the present invention, themethod comprises electrolessly depositing one or more metals such as,but not limited to, palladium, nickel, chromium, molybdenum, tungsten,iron, ruthenium, osmium, cobalt, rhodium, iridium, platinum, zinc,silver, copper, gold, or mixtures thereof. Optionally, the catalyst maybe produced as a single metal catalyst, as a bi-metallic catalyst, or asa tri-metallic catalyst. For embodiments of the present invention thathave two or more metals, optionally the metals may be mixed so that theyform an alloy or the elements may be present as substantially pureelements. The deposition of two or more metals may be done asco-deposition or as sequential deposition of the metals.

According to one embodiment of the present invention, the methodcomprises electroless deposition of palladium formed as nanoscalepalladium deposited on the substrate surfaces including, but not limitedto, the surfaces of pores.

According to one or more embodiments of the present invention, the metalis electrolessly deposited using electroless deposition processes sothat the metal is substantially free of electroless depositionimpurities. In one or more embodiments of the present invention, themethod electrolessly deposited metal using reducing agents such as, butnot limited to, hydrazine, aldehydes, carboxylic acids with up to 6carbon atoms, or mixtures thereof. According to one embodiment of thepresent invention, the method comprises adding hydrazine incrementallyor continuously during the deposition so that the reducing agent inputis distributed over most or all of the duration of the deposition.

According to one embodiment of the present invention, the methodincludes electroless deposition to accomplish a metal loading of lessthan 15% by weight. According to another embodiment of the presentinvention, the method includes electroless deposition to accomplish ametal loading of less than 5% by weight. According to yet anotherembodiment of the present invention, the method includes electrolessdeposition to accomplish a metal loading of less than 1% by weight.

According to one or more embodiments of the present invention, themethod further comprises sensitizing the substrate prior to electrolessdeposition such as by, but not limited to, exposing the substrate to asensitizing solution, exposing the substrate to a solution comprising adissolved metal, and/or exposing the substrate to a tin chloridesolution.

According to one or more embodiments of the present invention, themethod further comprises activating the substrate prior to electrolessdeposition such as by, but not limited to, exposing the substrate to anactivating solution, exposing the substrate to a solution comprising adissolved metal, and/or exposing the substrate to a palladium chloridesolution.

According to one or more embodiments of the present invention, themethod further comprises sensitizing the substrate prior to electrolessdeposition by exposing the substrate to a tin chloride solution followedby activating the substrate by exposing the substrate to a palladiumchloride solution.

According to one or more embodiments of the present invention, themethod uses a substrate that comprises activated carbon, carbon foam,alumina, metal foam, silica-alumina, silica, zeolites, titania,zirconia, magnesia, chromia, monoliths, or combinations thereof andelectrolessly deposits metal that comprises chromium, molybdenum,tungsten, iron, ruthenium, osmium, cobalt, rhodium, iridium, platinum,zinc, copper, gold, silver, or mixtures thereof using a reducing agentthat comprises hydrazine, aldehydes, carboxylic acids having 1-6 carbonatoms, or mixtures thereof.

According to one or more embodiments of the present invention, themethod comprises providing a substrate that comprises granular activatedcarbon, exposing the substrate to a tin chloride solution so as tosensitize the activated carbon for electroless deposition, and exposingthe substrate to a palladium chloride solution so as to activate theactivated carbon for electroless deposition. The method also includesproviding a solution of palladium for electroless deposition and mixingthe substrate with the solution. The method further includes controllingthe temperature of the mixture of the substrate and the solution andramping up the temperature while adding hydrazine incrementally orcontinuously so as to cause controlled electroless deposition of thepalladium as a catalytically active nanoscale coating of the activatedcarbon.

According to one or more embodiments of the present invention, themethod comprises providing a substrate that comprises granular activatedcarbon, exposing the substrate to a tin chloride solution so as tosensitize granular activated carbon for electroless deposition, andexposing the substrate to a palladium chloride solution so as toactivate the granular activated carbon for electroless deposition. Themethod also includes providing a solution of nickel for electrolessdeposition and mixing the substrate with the solution. The methodfurther includes controlling the temperature of the mixture of thesubstrate and the solution and ramping up the temperature while addinghydrazine incrementally or continuously so as to cause controlledelectroless deposition of the nickel as a catalytically active nanoscalecoating of the granular activated carbon.

Example 1 Catalyst Preparation—Palladium on Activated Carbon

FIG. 3 shows a flowchart of the steps for preparing the catalysts of thepresent example. Steps 101 to 104 constitute substrate preparation andare described as follows: Step 101: 14 grams of coconut activated carbon(CAC) in granular form with size in the range of 1.6 mm to 0.8 mm weremeasured using an analytical balance. Step 102: The CAC was placed inaluminum weighing dish and placed in a vacuum oven. The oven temperaturewas raised and maintained at 125° C. The CAC was baked for 12 hours.Step 103: Nitrogen gas was vented into the vacuum oven to reachatmospheric pressure. The CAC sample was taken out of oven andimmediately weighed on the analytical balance to obtain the actualweight of the CAC without moisture. Step 104: The CAC sample was placedin glass beaker with a magnetic stirrer and mixed with 50 ml of 0.2 NHCl acid for 30 minutes. The CAC sample was filtered from the acidsolution.

Steps 105 to 108 constitute substrate sensitizing and activation and aredescribed as follows: Step 105: In the sensitizing glass beaker, 125 mlof 0.2N HCl was mixed with 0.125 g SnCl₂ until the particles are fullydissolved using the magnetic stirrer. In the activation glass beaker,125 ml of 0.2 N HCl was mixed with 0.01125 g PdCl₂ until the particleswere fully dissolved using the magnetic stirrer. The CAC sample was putinto the sensitizing beaker and mixed for 5 minutes. The CAC sample wasfiltered from the sensitizing solution. Step 106: The CAC sample wasmixed in 500 ml of deionized (DI) H₂O for 10 minutes. The CAC sample wasfiltered from the DI H₂O. Step 107: The CAC sample was put into theactivation beaker and mixed for 5 minutes. The CAC sample was filteredfrom the activation solution. Step 108: The CAC sample was mixed in 500ml of deionized (DI) H₂O for 10 minutes. The CAC sample was filteredfrom the DI H₂O.

Steps 109 to 112 constitute plating of Pd on an activated carbonsubstrate and are described as follows: Step 109: In a glass beaker forplating solution, 70 ml of 28% NH₄OH, 30 ml DI H₂O, 0.54 g of PdCl₂, and4 g Na₂EDTA were mixed with a magnetic stirrer until the platingsolution was fully dissolved. The temperature of the water bath of theRotovap was raised to 40° C.; 0.1 ml of 35% N₂H₄ was added to theplating solution and mixed. The plating solution was combined with theCAC sample in a flask attached to the water bath in the Rotovap. Therotation was adjusted to evenly distribute the CAC in the platingsolution.

After 10 minutes, one drop of N₂H₄ was added to the plating solution andthe temperature was increased to 45° C. while the plating solution andCAC were continually mixed. After 20 minutes, one drop of N₂H₄ was addedto the plating solution and the temperature was increased to 50° C.while the plating solution and CAC were continually mixed. After 30minutes, the rotovap rpm was reduced to zero, the water-heating bath wasturned off and the plating flask was removed.

The Pd deposited CAC was filtered from the plating solution. Step 110:The CAC sample was mixed in 500 ml of deionized (DI) H₂O for 30 minutes.The Pd deposited CAC sample was filtered from the DI H₂O. The Pddeposited CAC sample was mixed in 500 ml of deionized DI H₂O for 30minutes. The Pd deposited CAC sample was filtered from the DI H₂O. Step111: The Pd deposited CAC was placed in an aluminum weighing dish andplaced in a vacuum oven. The vacuum pump was turned on and a vacuum of25 inches of Hg was maintained in the vacuum oven. The oven temperaturewas raised and maintained at 125° C. The Pd deposited CAC was baked for12 hours. Step 112: Nitrogen gas was vented into the vacuum oven untilatmospheric pressure was reached. The Pd deposited CAC sample was takenout of the oven and immediately weighed on the analytical balance toobtain the actual weight of Pd deposited CAC without moisture. Theweight difference between step 112 and step 103 represents the quantityof Pd deposited onto 14 grams of coconut activated carbon.

Methods of making catalysts according to one or more embodiments of thepresent invention may comprise using other granular, pelletized, orstructured substrates derived from ceramics or metal. Methods accordingto one or more embodiments of the present invention may comprise using astructured substrate such as monolith or metal foam for variousapplications.

Example 2 Catalyst Preparation—Palladium on Alumina

Extrudated gamma-alumina substrate material was crushed using a ceramicmortar and pestle and sifted to obtain particles in the size range of1.6 mm to 0.8 mm. An analytical balance was used to measure 14 grams ofthis gamma alumina substrate. The gamma alumina was baked in a vacuumoven for 12 hours and the dry weight of the gamma alumina substrate wasobtained from the analytical balance. The gamma alumina was hydrated bybeing exposed to steam for 2 hours to minimize gamma aluminadecrepitation prior to the sensitizing step.

In the sensitizing glass beaker, 125 ml of 0.2N HCl was mixed with 0.125g SnCl₂ until the particles were fully dissolved using a magneticstirrer. In the activation glass beaker, 125 ml of 0.2 N HCl was mixedwith 0.01125 g PdCl₂ until the particles were fully dissolved using amagnetic stirrer.

The gamma alumina sample was put into a sensitizing beaker and mixed for5 minutes. The gamma alumina sample was filtered from the sensitizingsolution. The gamma alumina sample was mixed in 500 ml of DI H₂O for 2minutes. The gamma alumina sample was filtered from the DI H₂O. Thegamma alumina sample was put into an activation beaker and mixed for 5minutes. The gamma alumina sample was filtered from the activationsolution. The gamma alumina sample was mixed in 500 ml of deionized DIH₂O for 2 minutes. The gamma alumina sample was filtered from the DIH₂O. The gamma alumina was put back into the sensitizing beaker andmixed for 5 minutes, filtered, and rinsed in DI H₂O for 2 minutes andfiltered. The gamma alumina was put back into the activation beaker andmixed for 5 minutes, filtered, and rinsed in DI H₂O for 2 minutes andthe gamma alumina was filtered out.

In a glass beaker for plating solution, 70 ml of 28% NH4OH, 30 ml DIH₂O, 0.54 g of PdCl₂, and 4 g Na₂EDTA were mixed until the platingsolution was fully dissolved. The temperature of water bath of BuchiRotovap was raised to 40° C. 0.1 ml of 35% N₂H₄ was added to the platingsolution and mixed well. The plating solution and gamma alumina samplewas combined in a flask and attached to the water bath in the BuchiRotovap. The rotation was adjusted to evenly distribute the gammaalumina in the plating solution. After 10 minutes, one drop of N₂H₄ wasadded to the plating solution and the temperature was increased to 45°C. while the plating solution and gamma alumina were continually mixed.After 5 minutes, the rotovap rpm was reduced to zero, the water-heatingbath was turned off, and the plating flask was removed. The Pd depositedgamma alumina was filtered from the plating solution.

The Pd deposited gamma alumina sample was mixed in 500 ml of deionized(Di) H₂O for 10 minutes. Pd deposited gamma alumina sample was filteredfrom the DI H₂O. Pd deposited gamma alumina was placed in aluminumweighing dish and placed in a vacuum oven. The vacuum pump was turned onand a vacuum of 25 inches of Hg was maintained in the vacuum oven. Theoven temperature was raised and maintained at 125° C. The Pd depositedgamma alumina was baked for 12 hours.

Nitrogen gas was vented into the vacuum oven to reach atmosphericpressure. The Pd deposited gamma alumina sample was taken out of ovenand immediately weighed on the analytical balance to obtain the actualweight of the Pd deposited gamma alumina without moisture. The weightdifference before and after Pd plating represents the quantity of Pddeposited onto 14 grams of gamma alumina.

Example 3 Catalyst Preparation—Nickel on Activated Carbon

Twenty-two grams of coconut activated carbon in granular form with sizein the range of 1.6 mm to 0.8 mm were measured using analytical balance.The CAC was placed in aluminum weighing dish and placed in vacuum oven.The vacuum pump was turned on and a vacuum of 25 inches of Hg wasmaintained in the vacuum oven. The oven temperature was raised andmaintained at 125° C. The CAC was baked for 12 hours. Nitrogen gas wasvented into vacuum oven to reach atmospheric pressure. The CAC samplewas taken out of oven and immediately weighed on the analytical balanceto obtain actual weight of CAC without moisture.

The CAC sample was placed in glass beaker with a magnetic stirrer andmixed with 60 ml of 0.2 N HCl acid for 5 minutes. The CAC sample wasfiltered from the acid solution. The above rinse was repeated 4 moretimes, each time with a new 60 ml of 0.2 NHCl.

In the sensitizing glass beaker, 185 ml of 0.2N HCl was mixed with 0.375g SnCl₂ until the particles were fully dissolved. In the activationglass beaker, 185 ml of 0.2 N HCl was mixed with 0.0341 g PdCl₂ untilthe particles were fully dissolved using a magnetic stirrer. The CACsample was put into a sensitizing beaker and mixed for 5 minutes. TheCAC sample was filtered from the sensitizing solution. The CAC samplewas mixed in 500 ml of deionized (Di) H₂O for 5 minutes. The CAC samplewas filtered from the DI H₂O.

The CAC sample was put into an activation beaker and mixed for 5minutes. The CAC sample was filtered from the activation solution. TheCAC sample was mixed in 500 ml of deionized (DI) H₂O for 10 minutes. TheCAC sample was filtered from the DI H₂O.

In a glass beaker for plating solution, 53 ml of 28% NH4OH, 90 ml DIH₂O, 0.8102 g of NiCl₂, and 6 g Na₂EDTA was mixed with a magneticstirrer until the plating solution was fully dissolved. The temperatureof a 1000 ml beaker water bath was raised to 60° C. using an IKAmagnetic stirrer hot plate. 0.1 ml of 35% N₂H₄ was added to the platingsolution and mixed well.

The CAC sample was put into a 250 ml beaker and the 250 ml beaker wassuspended into the IKA controlled water bath using rubber spacers at thetop of the water bath beaker. Mixing for the water bath was achieved bymagnetic stirrer. Mixing for the plating beaker was achieved with an IKAoverhead stirrer equipped with Teflon lined shaft and propellers (onemarine propeller and one turbine propeller). The plating beaker alsocontained 3 Teflon baffles attached together and oriented 120 degreesapart. The plating solution was poured into a 250 ml beaker containingthe CAC sample. The IKA mixer rpm was adjusted in the range of 200-400in order to evenly distribute the CAC in plating solution.

After 10 minutes, one drop of N₂H₄ was added to plating solution and thetemperature was increased to 65° C. while the plating solution and CACwere continually mixed. After 13 minutes, one drop of N₂H₄ was added tothe plating solution and the temperature was increased to 70° C. whilethe plating solution and CAC were continually mixed. After 10 minutes,one drop of N₂H₄ was added to the plating solution and the temperaturewas increased to 75° C. while the plating solution and CAC werecontinually mixed. After 14 minutes, one drop of N₂H₄ was added to theplating solution and the temperature was increased to 79° C. while theplating solution and CAC were continually mixed. After 5 minutes, onedrop of N₂H₄ was added to the plating solution and the temperature wasincreased to 79.5° C. while the plating solution and CAC werecontinually mixed. After 5 minutes, one drop of N₂H₄ was added to theplating solution and the temperature was increased to 80° C. while theplating solution and CAC were continually mixed. After 5 minutes, onedrop of N₂H₄ was added to the plating solution and the temperature wasincreased to 82° C. while the plating solution and CAC were continuallymixed. After 5 minutes, the rpm was reduced to zero, the water bathheating was turned off, and the plating flask was removed. The Nideposited CAC was filtered from the plating solution.

The CAC sample was gently mixed in 100 ml of deionized (DI) H₂O for 5minutes. The Ni deposited CAC sample was filtered from the DI H₂O. A 100ml water rinse was repeated as many times as necessary until the pH ofthe rinse solution reached 7. The Ni deposited CAC sample was filteredfrom the DI H₂O.

The Ni deposited CAC was placed in aluminum weighing dish and placed ina vacuum oven. The vacuum pump was turned on and a vacuum of 25 inchesof Hg was maintained in the vacuum oven. The oven temperature was raisedand maintained at 125° C. The Ni deposited CAC was baked for 12 hours.

Nitrogen gas was vented into vacuum oven to reach atmospheric pressure.The Ni deposited CAC sample was taken out of oven and immediatelyweighed on the analytical balance to obtain the actual weight of Nideposited CAC without moisture. The weight difference before and afterthe plating step represents the quantity of Ni deposited onto 22 gramsof coconut activated carbon.

Methods of Deoxygenation

Another aspect of the invention is a method of deoxygenation.Deoxygenation can occur by three mechanisms, which includehydrodeoxygenation where oxygen is mostly removed as H₂O,decarbonylation where oxygen is mostly removed as CO, anddecarboxylation where oxygen is mostly removed as CO₂. Conventionalhydroprocessing methods and catalyst used in deoxygenation will resultin high hydrogen consumption and high water production.

One or more embodiments of the present invention comprises using one ormore catalysts as described above. The selected catalyst is suitable forapplications such as, but not limited to, hydrogenation, anddeoxygenation of oxygenated hydrocarbons such as components of bio-oils.According to one or more embodiments of the present invention, thecatalysts have properties so that there is low or minimal undesirableby-product formation. Optionally, one or more embodiments of the presentinvention comprises using granular catalysts with low metal loading; thecatalysts are effective for reactions such as, but not limited to,hydrogenation and deoxygenation of organic materials such as, but notlimited to, bio-oils. One or more embodiments of the present inventioninclude using a reactor with the granular catalyst in a packed bed, thereactor and packed bed are arranged to operate in continuous multiphaseflow mode.

According to one embodiment of the present invention for deoxygenatinghydrocarbons, the method comprises providing a catalyst that comprises aporous substrate and an electrolessly deposited catalytically effectivenanoscale metal coating on the substrate. The method also includescontacting the catalyst with the oxygenated hydrocarbons and hydrogen soas to accomplish hydrogenation and deoxygenation wherein thedeoxygenation is accomplished preferentially by decarbonylation anddecarboxylation over hydrodeoxygenation.

According to one embodiment of the present invention, the methodaccomplishes a ratio of decarbonylation to decarboxylation of about 6:1.In other words, the method includes generating 6 times more carbonmonoxide than carbon dioxide for the deoxygenation. These results areextraordinary in comparison to the results of other processes. Othershave reported that the primary removal of oxygen is by production ofcarbon dioxide and/or water. Unlike embodiments of the presentinvention, other processes appear to have low production of carbonmonoxide.

The results of the present invention are even more extraordinary becausethe high production levels of carbon monoxide occur even with the use ofpalladium as the metal for the catalyst. Palladium is well known tothose of ordinary skill in the art as being particularly susceptible topoisoning by carbon monoxide. Experimental results obtained usingembodiments of the present invention show that the palladium catalystmaintained its catalytic activity even in the presence of carbonmonoxide at partial pressures as high as 0.1 megapascals for testedperiods of operation as long as 100 hours.

Deoxygenation processes according to methods of the present inventionmay include the use of variety of substrates for the catalyst. Examplesof suitable substrates for embodiments of the present invention include,but are not limited to, activated carbon, carbon foam, alumina, metalfoam, silica, silica-alumina, zeolites, titania, zirconia, magnesia,chromia, monoliths, or combinations thereof. Optionally, substrates forone or more embodiments of the present invention may be granular orpelletized.

According to one or more embodiments of the present invention, thedeoxygenation process uses a substrate having pores 0.2 nm to 10 nmwide. According to another embodiment of the present invention, thesubstrate has pores 0.2 nm to 10 nm wide and the metal is present in thepores.

According to one or more embodiments of the present invention, thecatalyst used for the deoxygenation process comprises one or more metalssuch as, but not limited to, palladium, nickel, chromium, molybdenum,tungsten, iron, ruthenium, osmium, cobalt, rhodium, iridium, platinum,zinc, silver, copper, gold, or mixtures thereof. Optionally, thecatalyst may be configured as a single metal catalyst, as a bi-metalliccatalyst, or as a tri-metallic catalyst. For embodiments of the presentinvention that have two or more metals, optionally the metals may bemixed so that they form an alloy or the elements may be present assubstantially pure elements.

According to one embodiment of the present invention, the metalcomprises palladium formed as nanoscale palladium deposited on thesubstrate surfaces including, but not limited to, the surfaces of pores.Metals other than palladium may be used in the catalytic materials forone or more embodiments of the present invention. Substrates for one ormore embodiments of the present invention include activated carbon suchas coconut activated carbon.

According to one or more embodiments of the present invention, the metalis electrolessly deposited using electroless deposition processes sothat the metal is substantially free of electroless depositionimpurities. In one or more embodiments of the present invention, metaldeposition is electroless deposition accomplished with reducing agentssuch as, but not limited to, hydrazine, aldehydes, carboxylic acids withup to 6 carbon atoms, or mixtures thereof. According to one embodimentof the present invention, the metal deposition is accomplished withhydrazine incrementally or continuously added during the deposition sothat the reducing agent input is distributed.

According to one embodiment of the present invention, the loading of themetal is less than 15% by weight. According to another embodiment of thepresent invention, the loading of the metal is less than 5% by weight.According to yet another embodiment of the present invention, theloading of the metal is less than 1% by weight.

According to one or more embodiments of the present invention, thecatalyst is catalytically active for deoxygenation of molecules such asoxygenated hydrocarbons. An exceptional and unexpected property ofcatalyst according to one or more embodiments of the present inventionis that the catalyst is catalytically active for preferentialdeoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation. Preferential deoxygenation by decarbonylation anddecarboxylation over hydrodeoxygenation is defined as greater than orequal to 60% of oxygen is removed from oxygenated hydrocarbon as carbondioxide and carbon monoxide and less than or equal to 40% of the oxygenis removed as water.

According to another embodiment of the present invention, the catalystis catalytically active so as to be capable of preferentialdeoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation of alcohols, ethers, aldehydes, ketones, carboxylicacids, phenolics, esters, or mixtures thereof by decarbonylation anddecarboxylation over hydrodeoxygenation. Catalysts, according to one ormore embodiments of the present invention, are capable of hydrogenationand preferential deoxygenation of triglycerides by decarbonylation anddecarboxylation over hydrodeoxygenation.

According to another embodiment of the present invention, the activationenergy for deoxygenation is about 54 kcal/g-mole for Camelina oil.According to another embodiment of the present invention, the metalcomprises palladium, the substrate has pores 0.2 nm to 10 nm wide withthe metal present therein, and the catalyst is active for deoxygenationof triglycerides. According to another embodiment of the presentinvention, the catalyst is catalytically active for hydrogenation andpreferential deoxygenation of triglycerides by decarbonylation anddecarboxylation over hydrodeoxygenation so that the ratio of odd carbonnumber molecules to even carbon number molecules in the deoxygenatedproduct is about 6:1.

Another embodiment of the present invention is a catalyst fordeoxygenating bio-oils for fuel production. The catalyst comprises asubstrate comprising activated carbon in granular form with size in therange of 0.5 mm to 3 mm. The substrate has pores 0.2 nm to 10 nm wide.The catalyst comprises an electrolessly deposited catalyticallyeffective palladium or nickel coating having nanoscale thicknessdisposed on the surfaces of the pores. The palladium or nickel loadingfor the catalyst is less than about 2% by weight. Optionally, the metalcomprises palladium grains about 15 nanometers wide.

According to another embodiment of the present invention, the metalcoating of the catalyst is palladium and the method of deoxygenation isperformed with the catalyst exposed to carbon monoxide partial pressureup to about 0.1 megapascals. As an option for one or more embodiments ofthe present invention, the oxygenated hydrocarbons comprisetriglycerides, the substrate is activated carbon, and the metalcomprises palladium. The method further includes contacting the catalystwith the oxygenated hydrocarbons and hydrogen so as to preferentiallyaccomplish deoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation. The deoxygenation is accomplished at temperatures inthe range 300° C. to 400° C. and pressures in the range 1.5 megapascalsto 15 megapascals.

A method of deoxygenation according to another embodiment of the presentinvention, the hydrocarbons comprise triglycerides, the substratecomprises activated carbon, carbon foam, alumina, metal foam,silica-alumina, silica, zeolites, titania, zirconia, magnesia, chromia,monoliths, or combinations thereof. The metal is selected from the groupconsisting of chromium, molybdenum, tungsten, iron, ruthenium, osmium,cobalt, nickel, rhodium, iridium, palladium, platinum, zinc, gold,silver, copper, or mixtures thereof, and contacting the catalyst withthe oxygenated hydrocarbons and hydrogen so as to preferentiallyaccomplish deoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation is accomplished at temperatures in the range 300° C.to 400° C. and pressures in the range 1.5 megapascals to 15 megapascals.Optionally, the catalyst has a metal loading of less than or equal toabout 2% with deoxygenation efficiency greater than about 90% or thecatalyst has a metal loading of less than or equal to about 1% withdeoxygenation efficiency greater than about 90%. For one or moreembodiments of the present invention, the method includes using a weighthourly space velocity of 0.2 to 2.5. The weight hourly space velocity iscalculated as the mass flow rate of the feed divided by the mass ofcatalyst.

Example 4 Deoxygenation Using Palladium on Activated Carbon

Using methods according to one or more embodiments of the presentinvention, catalysts were made with different Pd metal loading oncoconut activated carbon. The catalysts were placed in a packed bedreactor with the same operating parameters processing Camelina oil incontinuous multiphase flow mode. The results that were obtained wereexceptional and unexpected with respect to the low metal loading andhigh percentage of deoxygenation. Table 1 shows that high deoxygenationcan be achieved at low metal loading:

TABLE 1 Palladium Loading (wt %) Deoxygenation (%) 0.5 86 1.2 91 3.0 875.2 84

In another experiment using catalysts according to one or moreembodiments of the present invention, catalysts with average metalloading of 5 weight % was made and loaded into a packed bed reactor toprocess Camelina oil in continuous operation for 100 operating hours.Sustained deoxygenation activity was observed over the duration of thecontinuous operation.

Palladium catalyst prepared according to one or more embodiments of thepresent invention may have significant cost advantages that can begained by using lower metal loading to carry out deoxygenation ofbio-oils. Catalysts according to one or more embodiments of the presentinvention, when used to carry out deoxygenation reaction, did not showany plugging or coking issues throughout a 500-hour continuous run in apacked bed reactor. Catalysts according to one or more embodiments ofthe present invention achieve deoxygenation primarily throughdecarbonylation chemistry as evident by CO content in reactor gas outletcomposition.

Experimental work was done using a continuous flow fixed bed reactoraccording to one or more embodiments of the present invention. Thereactor was a 0.305 inch internal diameter, 10 inch long reactor withpre-heat and post-heat zones. Reactor volume was 12 cc with a catalystweight of 6.13 g. Experiments were done and results were obtained for arange of conditions. Some of the parameters varied were temperature,pressure, and space velocity. Ranges covered and results were:

Temperature range 300-400 C

Pressure 250-1000 psig

Weight Hourly Space Velocity (WHSV) 0.5 to 2.5

Conversion 20-95%

Methods of deoxygenation according to one or more embodiments of thepresent invention comprise using palladium catalyst material finelydispersed on activated carbon which may be prepared as described above.According to one or more embodiments, the method uses the fine porestructure of the activated carbon. The method uses relatively highertemperatures to effectively hydrogenate and split feed molecules so thatthe fragments have easy access to the fine pore structure of thesubstrate.

The inventors have also used one or more embodiments of the presentinvention in test for 100 hours of continuous flow operation fordeoxygenation of Camelina oil and showed that sustained catalystactivity was achieved under smooth reactor operation with no evidence ofplugging or coking. In contrast, other deoxygenation technologies havebeen reported to produce high contents of aromatics and unsaturatesresulting in coking and plugging of the deoxygenating reactor incontinuous flow operating mode.

The method of preparing the catalysts, such as the method describedabove, allows penetration of nanocrystalline palladium into microporesof 0.4 to 2 nanometers. Small pore volume offers the most surface areafor reactions. Methods according to one or more embodiments of thepresent invention have shown that large concentration of palladium isnot needed in the catalysts, which is a result that is unexpected andexceptional and may be the result of having deposited the palladiumperhaps substantially as a nanoscale coating.

As stated above, catalysts having from 0.5% to 5% palladium loading weretested. The catalyst showed very little effect of catalytic metalloading on deoxygenation activity (see Table 1). For one or moreembodiments of the present invention, the specific substrate-activemetal combination appears to promote decarbonylation of oils, such asplant oils, in preference to hydrodeoxygenation in removing oxygen fromthe oil molecule. This is highly advantageous in process design forapplications such as converting plant oils to biofuels and is anexceptional and unexpected result.

When oxygen is removed as oxides of carbon, the product molecule willhave one less carbon. For example, C18 molecule will become C17. Thefeed molecule as shown in FIG. 1-2 has C16, C18, C20, C22, and C24molecules, all even numbered. FIG. 1-3 is a gas chromatograph traceshowing the composition of deoxygenated product produced according toone or more embodiments of the present invention. As the gaschromatograph shows, odd number carbon atoms dominate to the extent theratio of odd and even number atoms is about 6 to 1. In contrast to theresults obtained using embodiments of the present invention, datareported for other processes show that the ratio of odd to even numbercarbon species is in the range from 0 to 1.

As hydrodeoxygenation is suppressed, hydrogen consumption will beminimized and less water will be made in the reactor. High hydrogenconsumption adversely affects the operating cost of the plant and italso puts a new demand on hydrogen in an existing refinery. Mostrefineries lack adequate supply of hydrogen and building new hydrogenplant for retrofit are usually cost prohibitive. In such situations, aprocess that doesn't consume large quantities of hydrogen offers greateconomic and logistic advantages to a refiner planning to producebiofuels with existing refinery infrastructure.

Another drawback of a process that consumes considerable amounts ofhydrogen is reactor temperature control. Hydrogen, when consumed,releases a significant amount of heat and this has to be efficientlyremoved for safety and proper operation of the plant.

One or more embodiments of the present invention result in about 60-65%of oxygen removed as oxides of carbon with only about one third going tomake water. This is an unexpected and extraordinary result for one ormore embodiments of the present invention.

One or more embodiments of the present invention comprises using areactor space velocity that may be higher than in a typicalhydroprocessing unit commonly used in petroleum refining. Processesaccording to one or more embodiments of the present invention use modesttemperatures and modest hydrogen pressure. According to one embodimentof the present invention, the process includes using a conventionaldownflow fixed bed reactor. The option to use a fixed bed reactor makesthe process easy to scale-up. Preferred embodiments of the presentinvention do not use a solvent during deoxygenation processes.

Example 5 Deoxygenation Using Palladium on Alumina Catalyst

Refined Camelina oil was the feedstock used in a deoxygenation reactoraccording to one or more embodiments of the present invention.Deoxygenation experiments were carried out in a continuous down-flowmultiphase packed bed reactor. In this example, 6.1 grams of 0.5 wt % Pdon gamma alumina catalyst according to one or more embodiments of thepresent invention was loaded into a stainless steel reactor. The reactorwas 0.305 inches in internal diameter and 10 inches in length withpre-heat and post-heat zones. The reactor volume was 12 cc. Heat for thereactor was supplied by a 3-zone temperature controlled furnace withheat equalizing blocks. Camelina oil feed was pumped at a 0.1 cc/minrate into the reactor. Liquid and gaseous products exiting the reactorwere collected in a separator. Backpressure regulators maintainedoperating system pressure at 500 psig. The Pd on gamma alumina catalystwas reduced under hydrogen at 250° C. for 2 hours to activate thecatalyst. Reactor temperature was raised from 250° C. to 350° C. within60 minutes. Liquid Camelina oil feed was then pumped into the reactor ata 0.1 cc/min rate. Hydrogen gas feed rate into the reactor was 70cc/min. The reactor temperature was maintained at 350° C. and thereactor was run for 10 hours. The reactor gas product was analyzed usinga gas chromatograph. The major reactant gaseous product observed otherthan H₂ was CO. Paraffinic wax product was separated from water bygravity. Elemental analysis was performed on the parrafinic wax productto determine the oxygen content of deoxygenated product. Oxygenelemental analysis showed approximately 96% of oxygen had been removedfrom the original Camelina oil feed.

Example 6 Deoxygenation Using Nickel on Activated Carbon Catalyst

Refined Camelina oil was the feedstock used in deoxygenation micro unitaccording to one or more embodiments of the present invention.Deoxygenation experiments were carried out in a continuous down-flowmultiphase packed bed reactor. In this example, 6.1 grams of 0.9 wt % Nion activated carbon catalyst according to one or more embodiments of thepresent invention was loaded into a stainless steel reactor. The reactorwas 0.305 inches in internal diameter and 10 inches in length withpre-heat and post-heat zones. The reactor volume was 12 cc. Heat for thereactor was supplied by a three-zone temperature controlled furnace withheat equalizing blocks. Liquid and gaseous products exiting the reactorwere collected in a separator. Backpressure regulators maintainedoperating system pressure at 1000 psig. The Ni on the activated carboncatalyst was reduced under hydrogen at 250° C. for 2 hours to activatethe catalyst. The Ni catalyst was used in bare metal form instead of asa sulfide form that is typical for the hyproprocessing industry. Reactortemperature was raised from 250° C. to 360° C. within 60 minutes. LiquidCamelina oil feed was then pumped into the reactor at a 0.1 cc/min rate.The hydrogen gas feed rate into the reactor was 168 cc/min. Reactortemperature was maintained at 360° C. and the reactor was run for 13hours. Reactor gas product was analyzed using a gas chromatograph. Themajor reactant gaseous product observed other than H₂ was CO. Paraffinicwax product was separated from water by gravity. Elemental analysis wasperformed on the parrafinic wax product to determine the oxygen contentof deoxygenated product. Oxygen elemental analysis showed approximately87% of oxygen had been removed from the original Camelina oil feed.

Catalysts according to one or more embodiments of the present inventionpromote decarbonylation and decarboxylation rather thanhydrodeoxygenation. The process consumes considerably less hydrogen forone or more possible benefits such as, but not limited to, favorableprocess economics, use of existing refinery infrastructure to producesynthetic biofuels, and easier reactor design. Furthermore, one or moreprocesses according to embodiments of the present invention comprises ahigh yield of distillate fuels with low or minimal production ofundesired by-products. Deoxygenation reactors according to embodimentsof the present invention comprise one or more of multiphase downflowpacked bed configuration, continuous flow operation capability, and theabsence of extraneous or process derived solvents or diluents.

Methods of Fuel Production

A part of the process of producing synthetic biofuels from biosources isdeoxygenation. Deoxygenation can occur by three mechanisms, whichinclude hydrodeoxygenation where oxygen is mostly removed as H₂O,decarbonylation to where oxygen is mostly removed as CO, anddecarboxylation where oxygen is mostly removed as CO₂. In other words,the processing of bio-oils which have a different chemistry thanconventional petroleum oils have one or more problems that are overcomeby one or more embodiments of the present invention.

Although embodiments of the present invention can efficiently convertany type of bio-oils and/or other suitable feedstocks, one or more ofthe following examples provide data for deoxygenation of non-ediblebio-oils. Examples of nonedible bio-oils include Tung, Jojoba, Jatropha,Camelina sativa, Tall, Crambe, Castor, Industrial Rapeseed, Cuphea,Lesquerella, and others. Advancements in genetics engineering offer thepossibilities for bio-oils to be extracted from oil seed crops that arehardy, drought tolerant, pest resistant, and can be grown on marginalsoil to provide high oil weight content. Alternatively, bio-oils canalso be extracted from algae and other genetically engineered biologicalsystems. Estimated bio-oil content from these sources can range from 25wt % to 50 wt %.

Reference is now made to FIG. 4 where there is shown a schematic diagramof a system 300 for producing fuels such as gasoline, diesel fuel, andjet fuel from sources such as, but not limited to, renewable feedstocks.System 300 comprises a deoxygenation stage 310 which comprises at leastone deoxygenation reactor chamber 315 and a catalyst 320 contained inthe deoxygenation reactor chamber 315. Catalyst 320 comprises a poroussubstrate and an electrolessly deposited metal coating having ananoscale thickness. Catalyst 320 according to one or more embodimentsof the present invention is essentially the same as catalysts describedearlier in the present disclosure. As an option for one or moreembodiments of the present invention, at least one deoxygenation reactorchamber 315 and the catalyst 320 are configured as a packed bed reactorto operate in continuous multiphase flow mode with hydrogen as areactant.

According to one embodiment of the present invention, the poroussubstrate of catalyst 320 has a surface area equivalent of 50-1500 m²/g.According to one or more other embodiments of the present invention, theporous substrate of catalyst 320 has a surface area equivalent in therange of 50-100 m²/g. According to one or more other embodiments of thepresent invention, the porous substrate of catalyst 320 has a surfacearea equivalent in the range of 100-300 m²/g. According to one or moreother embodiments of the present invention, the porous substrate ofcatalyst 320 has a surface area equivalent in the range of 300-900 m²/g.According to one or more other embodiments of the present invention, theporous substrate of catalyst 320 has a surface area equivalent in therange of 900-1500 m²/g.

A variety of substrates can be used for catalyst 320. Examples ofsuitable substrates for catalyst 320 include, but are not limited to,activated carbon, carbon foam, alumina, metal foam, silica,silica-alumina, zeolites, titania, zirconia, magnesia, chromia,monoliths, or combinations thereof. Optionally, substrates catalysts 320may be granular or pelletized.

According to one or more embodiments of the present invention, thesubstrate of catalyst 320 has pores 0.2 nm to 10 nm wide. According toanother embodiment of the present invention, the substrate of catalyst320 has pores 0.2 nm to 10 nm wide and the metal is present in thepores.

According to one or more embodiments of the present invention, catalyst320 comprises one or more metals such as, but not limited to, palladium(Pd), nickel (Ni), chromium (Cr), molybdenum (Mo), tungsten (W), iron(Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium(Ir), platinum (Pt), zinc (Zn), silver (Ag), copper (Cu), gold (Au), ormixtures thereof. Optionally, catalyst 320 may be configured as a singlemetal catalyst, as a bi-metallic catalyst, or as a tri-metalliccatalyst. For embodiments of the present invention that have two or moremetals, optionally the metals may be mixed so that they form an alloysuch as palladium and nickel in an alloy. Alternatively, the elementsmay be present as substantially pure elements.

According to one embodiment of the present invention, the metalcomprises palladium formed as nanoscale palladium deposited on thesubstrate surfaces including, but not limited to, the surfaces of pores.Metals other than palladium may be used in the catalytic materials forone or more embodiments of the present invention. Substrates for one ormore embodiments of the present invention include activated carbon suchas coconut activated carbon.

According to one or more embodiments of the present invention, the metalis electrolessly deposited using electroless deposition processes sothat the metal is substantially free of electroless depositionimpurities. In one or more embodiments of the present invention, metaldeposition is electroless deposition accomplished with reducing agentssuch as, but not limited to, hydrazine, aldehydes, carboxylic acids withup to 6 carbon atoms, or mixtures thereof. According to one embodimentof the present invention, the metal deposition is accomplished withhydrazine incrementally or continuously added during the deposition sothat the reducing agent input is distributed.

According to one embodiment of the present invention, the loading of themetal is less than 15% by weight. According to another embodiment of thepresent invention, the loading of the metal is less than 5% by weight.According to yet another embodiment of the present invention, theloading of the metal is less than 1% by weight.

According to one or more embodiments of the present invention, catalyst320 is catalytically active for deoxygenation of molecules such asoxygenated hydrocarbons. An exceptional and unexpected property ofcatalyst 320 according to one or more embodiments of the presentinvention is that the catalyst is catalytically active for preferentialdeoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation. Preferential deoxygenation by decarbonylation anddecarboxylation over hydrodeoxygenation is defined as greater than orequal to 60% of oxygen is removed from oxygenated hydrocarbon as carbondioxide and carbon monoxide and less than or equal to 40% of the oxygenis removed as water.

According to another embodiment of the present invention, catalyst 320is catalytically active so as to be capable of preferentialdeoxygenation by decarbonylation and decarboxylation overhydrodeoxygenation of alcohols, ethers, aldehydes, ketones, carboxylicacids, phenolics, esters, or mixtures thereof by decarbonylation anddecarboxylation over hydrodeoxygenation. Catalyst 320 according to oneor more embodiments of the present invention is capable of hydrogenationand preferential deoxygenation of triglycerides by decarbonylation anddecarboxylation over hydrodeoxygenation.

According to another embodiment of the present invention, the activationenergy for deoxygenation is about 54 kcal/g-mole for Camelina oil whenusing catalysts 320. According to another embodiment of the presentinvention, the metal of catalyst 320 comprises palladium, the substratehas pores 0.2 nm to 10 nm wide with the metal present therein, and thecatalyst is active for deoxygenation of triglycerides. According toanother embodiment of the present invention, catalyst 320 iscatalytically active for hydrogenation and preferential deoxygenation oftriglycerides by decarbonylation and decarboxylation overhydrodeoxygenation so that the ratio of odd carbon number molecules toeven carbon number molecules in the deoxygenated product is about 6:1.

Another embodiment of the present invention is a catalyst fordeoxygenating bio-oils for fuel production. Catalyst 320 comprises asubstrate comprising activated carbon in granular form with size in therange of 0.5 mm to 3 mm. The substrate has pores 0.2 nm to 10 nm wide.Catalyst 320 comprises an electrolessly deposited catalyticallyeffective palladium or nickel coating having nanoscale thicknessdisposed on the surfaces of the pores. The palladium or nickel loadingfor catalyst 320 is less than about 2% by weight. Optionally, catalyst320 comprises palladium grains about 15 nanometers wide.

As an option for one or more embodiments of the present invention,system 300 further comprises a three-phase separator configured toreceive effluent from deoxygenation stage 310 and to separate water,liquid hydrocarbons, and gases from the effluent into separate streams.

According to one or more embodiments of the present invention, system300 further comprises a hydrocracking and isomerization stage 350comprising at least one hydrocracking and isomerization reactor 355 anda hydrocracking and isomerization catalyst 360. Hydrocracking andisomerization stage 350 is configured to receive the liquid hydrocarbonsfrom deoxygenation stage 310 and hydrogen. Hydrocracking andisomerization stage 350 operates at conditions to convert the liquidhydrocarbons from deoxygenation stage 310 into gasoline, diesel fuel,and/or aviation/jet fuel. More specifically, hydrocracking andisomerization stage 350 is configured to operate at temperatures andpressures to accomplish converting the hydrocarbons into the fuels.Hydrocracking and isomerization catalyst 360 may be one or morecommercially available catalyst for hydrocracking and isomerization.

According to one or more embodiments of the present invention,deoxygenation stage 310 comprises two or more deoxygenation reactorchambers 315 each containing catalyst 320. The two or more deoxygenationreactor chambers 315 are connected in series (not shown in FIG. 4).

According to one or more embodiments of the present invention,deoxygenation stage 310 comprises two or more deoxygenation reactorchambers 315 each containing catalyst 320 or a mixture of catalysts. Thetwo or more deoxygenation reactor chambers 315 are connected in seriesand system 300 further comprises a separator system to remove carbonmonoxide, light gases, carbon dioxide, and water from the effluentstream connecting the two or more deoxygenation reactor chambers 315between the two or more deoxygenation reaction chambers (additionalreaction chambers and separator not shown in FIG. 4).

According to another embodiment of the present invention, system 300further comprises a product separation stage 370 configured to receiveproducts from hydrocracking and isomerization stage 350 and separate theproducts into diesel fuel, gasoline, and/or aviation/jet fuel. System300 further comprises a separator 375 comprising more than oneseparation stage to separate hydrogen from hydrocracking isomerizationstage 350 effluent for recycle back to hydrocracking isomerization stage350.

Reference is now made to FIG. 5 where there is shown a system 400 forproducing fuel from feedstocks such as renewable feedstocks such as, butnot limited to, bio-oils and other oxygenated hydrocarbons. System 400comprises a deoxygenation stage 310, a three-phase separator 335, ahydrocracking and isomerization stage 350, a product separation stage370, and a separator 375 all substantially the same and configured asdescribed above for system 300. System 400 further comprises a separator410 configured to receive the gases from three phase separator 335 andto separate hydrogen from carbon monoxide, carbon dioxide, and lightgases. Separator 410 is connected to provide hydrogen to deoxygenationstage 310 or to hydrocracking stage 350. System 400 further comprises asteam reformer and water gas shift stage 420 connected so as to receivecarbon monoxide, CO₂, and light gases from separator 410 and light gasesfrom product separation stage 370. Steam reformer and water gas shiftstage 420 produces hydrogen from the gases that it receives using watergas shift reactions and/or reformer and provides the hydrogen todeoxygenation stage 310 and/or hydrocracking and isomerization stage350.

According to another embodiment of the present invention, system 400comprises a three-phase separator 335 configured to receive effluentfrom the deoxygenation stage and to separate water, liquid hydrocarbons,and gases from the effluent into separate streams; and a secondseparator 410 and reformer/shift stage 420 to produce hydrogen from thecarbon monoxide and the light gases.

In one or more alternative embodiments of systems according to thepresent invention, the deoxygenation stage comprises two or moredeoxygenation reactor chambers connected in series and a separator toremove carbon monoxide, carbon dioxide, water, and light gases from thestream between the two or more deoxygenation reaction chambers. Anotherseparator is used to separate hydrogen from the carbon monoxide, thecarbon dioxide, and light gases. A reformer/shift reactor is included toproduce hydrogen from the carbon monoxide and the light gases.

According to one or more embodiments of the present invention, a basicprocess is to deoxygenate the naturally occurring, nonedible bio-oils oralgae oil to produce corresponding alkanes and further treat them toproduce specification biofuels. The treatment process involveshydrocracking and isomerization. One or more embodiments of the presentinvention include a two-stage process wherein the first process involvesdeoxygenating the oil using catalysts and operating conditions accordingto one or more embodiments of the present invention to suppress waterformation. The second stage of the process comprises hydroprocessing ofthe first stage product in a second stage reactor.

The total gas and liquid mixture from the first stage reactor is cooledand flashed to remove the gases and light liquid products, if any. Thethree-phase separator also removes any water produced in the first stagedeoxygenation reactor to avoid degradation of the second stage catalyst.

The hydrogen feed gas in the first-stage reactor is operated inonce-through mode. The gas mixture from the three-phase separator willcontain large amounts of CO and hydrogen besides CO₂ and other lighthydrocarbon product gases. The ratio of CO to CO₂ from the first-stageproduct gas mixture is significantly higher than reported in literatureby others. Thus, as an option for one or more embodiments of the presentinvention, this gas mixture can used as a source for hydrogen generationor used to produce the needed process heat.

Optionally, the product gas from the first stage after removal of waterand other heavy condensable (if any), can be further processed toseparate hydrogen from CO, CO₂, and light hydrocarbons. The recoveredhydrogen can then be returned to the reactor. The stream containing somehydrogen, CO, CO₂, and light hydrocarbon gases can be made to go throughsteam reforming and water-gas-shift reactions to produce hydrogen whichcan be used as make-up to both the first and the second stage reactors.If desired, the light hydrocarbon gas stream can be supplemented byaddition of some light liquid products from the process so as to meetthe total requirement of make-up hydrogen for the process. Anotheroption would be to use the separated CO, CO₂, and light hydrocarbon gasstream for combustion in a furnace to provide the necessary process heatto the unit. In this mode of operation, a single recycle gas stream andone recycled gas compressor can be used for both stages for furthersimplification of the overall flow scheme.

The liquid product from the first-stage deoxygenation reactor will beprimarily be a mixture of straight chain normal paraffins with a lowmelting point. These are mixed with a fresh stream of recycle hydrogenand passed through another fixed bed reactor to conduct isomerizationand mild hydrocracking reactions. Product from the second-stage reactorwill have hydrocarbon components that boil in the gasoline, jet, anddiesel range temperatures. A suitable commercially availablehydroprocessing catalyst that provides these functions is housed in thesecond-stage reactor.

According to one or more embodiments of the present invention, thefirst-stage deoxygenation reactor used deoxygenation catalyst accordingto one or more embodiments of the present invention made by processesaccording to one or more embodiments of the present invention. Thedeoxygenation process uses process conditions according to one or moreembodiments of the present invention.

Liquid product from the first-stage conversion, according to one or moreembodiments of the present invention, was analyzed using GC/MS and atrace for the liquid product from deoxygenation of Camelina oil is shownin FIG. 1-3. The GC trace showed that the paraffinic product primarilycontained paraffins with chain length that is one carbon less than theoriginal fatty acid composition when compared with FIG. 1-2. The resultsindicate that liquid product is primarily paraffinic product and alsoindicate that deoxygenation is mostly achieved through production of COand CO₂ rather than water.

The ratio of odd to even number carbon species in the liquid productfrom the first stage is an indicator of the predominant mechanism fordeoxygenation: decarbonylation, decarboxylation, or hydrodeoxygenation.The higher ratio indicates that the more predominant mechanism is thedecarbonylation or decarboxylation mechanism (producing oxides of carbonrather than water). Experimental results for embodiments of the presentinvention show this ratio is about 6 in the liquid product; however, inother deoxygenation technologies, the ratio is typically less than 1. Alow ratio is an indication that large quantities of water are producedby hydrodeoxygenation and the process consumes large quantities ofhydrogen.

The ratio of CO to CO₂ obtained using deoxygenation catalyst andprocesses according to one or more embodiments of the present inventionis approximately 6, which indicates that deoxygenation for embodimentsof the present invention is primarily as decarbonylation. For otherdeoxygenation technologies, the ratio of CO to CO₂ is from 0 to 2. Thehigher CO content in the gas product mixture has advantages for use asfuel and for hydrogen generation.

Hydroprocessing units and associated catalysts according to one or moreembodiments of the present invention are unique at least in part becauseof their capability to selectively convert different types of bio-oilsinto aviation and other transportation fuels with performancecharacteristics comparable to conventional petroleum based products.Long chain alkanes resulting from deoxygenation of oils can be crackedin the presence of hydrogen and catalysts to produce bio-jet fuel(boiling temperature range 118-314° C.) and bio-diesel fuel (boilingtemperature range 262-407° C.). Furthermore, the alkane chain can beisomerized to produce branched hydrocarbons. With the appropriatecommercial hydroprocessing catalyst, the product can be customized bycontrolling the degree of cracking and isomerization to produce“designer” bio-jet and bio-diesel fuels with specific desirableproperties.

One embodiment of the present invention is a process to produce dieseland aviation fuels from renewable bio-feedstocks. The specificbio-feedstocks are vegetable oils and cellulose-derived bio-oils.Pyrolysis, liquefaction, or microbial means can be used to producebio-oils from cellulosic materials like wood chips, farm residues, ormunicipal waste.

Whether it is crop oil or an oil derived from cellulosic material, theoil should pass though a pre-treating step to rid it of contaminants andpotential catalyst poisons. In the case of crop oils, the pre-treatingstep may only consist of acid washing steps and treatment with an ionexchange material. In the case of oil derived from cellulosicfeedstocks, extensive pre-treatment steps are needed to improve theirprocessibility. They should undergo significant upgrading to removecontaminants and to improve stability.

These oils, whether derived from crop oils or cellulosic bio-oils,consist of oxygen in significant amounts in addition to carbon andhydrogen in their constituent molecule. The process described hereconsists of steps to remove this oxygen. In the case of crop oils, oncethe oxygen is removed and the triglyceride backbone is broken, theresultant molecule is a straight-chain paraffin. The paraffin is furthersubjected to additional processing steps to yield a bio-fuel to meet allthe specifications of transportation fuels.

The process to convert renewable feedstocks like crop oils, therefore,consists of two process steps: oxygen removal and isomerization/mildcracking to produce the final biofuel product.

The first step consists of breaking the triglyride backbone,hydrogenating to saturate the molecule, and removing oxygen(deoxygenation) from the oil molecule. The deoxygenation is a catalyticreaction in the presence of a catalyst and hydrogen. Hydrogen is areactant. The catalyst is loaded into a continuous flow fixed bedreactor. Hydrogen gas and the bio-oil feedstock are mixed together aheadof the reactor, heated to reaction temperature in a feed furnace, andreacted in the continuous flow fixed bed reactor. A catalyst, such asthat according to one or more embodiments of the present invention, isloaded into the reactor and preferentially removes oxygen bydecarbonylation and decarboxylation rather than hydrodeoxygenation.Decarbonylation produces carbon monoxide, decarboxylation producescarbon dioxide, and hydrodeoxygenation produces water. It is preferableto remove oxygen by decarbonylation or decarboxylation rather than byhydrodeoxygenation. Hydrodeoxygenation consumes higher amounts ofhydrogen. Higher hydrogen consumption adversely affects the processeconomics.

Higher hydrogen consumption in the reactor also releases heat which hasto be removed for temperature control in the reactor. This would requirespecial design of reactor internals, adding to the cost and complexityof the process. Cold hydrogen gas is used to quench the reaction/productmixture between catalyst beds in a multi-bed reactor. Higher watergeneration in the reactor also can cause damage to the integrity andmechanical strength of the catalyst under certain situations.

Catalyst according to one or more embodiments of the present inventionused in the process preferentially removes oxygen by decarboxylation anddecarbonylation mechanism than by hydrodeoxygenation mechanism therebyproducing CO and CO₂ rather than water. Table 2 shows results from atypical run:

TABLE 2 PARAMETER Temperature (° C.) 380 380 Pressure (psig) 500 500WHSV (1/hr) 2.5 0.82 Hydrogen Feed (SCFB) 2878 9582 PRODUCTS CO/CO₂ (wt%) 8.78 9.96 Water (wt %) 2.57 2.79 Whole Liquid Product (wt %) 88.6587.25 Deoxygenation (wt %) 80.2 90.6

The total gas and liquid mixture from the reactor is cooled and flashedto remove the gases and light liquid products, if any. The liquidproduct will be primarily a mixture of straight chain normal paraffinswith a low melting point. These are mixed with a fresh stream of recyclehydrogen and passed through another fixed bed reactor to conductisomerization and mild hydrocracking reactions. A suitable catalyst thatprovides these functions is housed in this reactor. Product from thisreactor will have hydrocarbon components that boil in the gasoline, jet,and diesel range temperatures.

In isomerization and mild hydrocracking, the normal paraffins of 15 to23 carbon atoms undergo cracking and branching in the presence ofhydrogen. These types of reactions allow conversion of normal paraffinsto specification fuels boiling predominantly in the diesel and jetboiling range.

The gas-liquid mixture of the second-stage reactor effluent is flashedand the gaseous mixture which contains mostly hydrogen-rich gas iscleaned and recycled to the front end of the reactor for reuse. Hydrogenconsumed in both first and second stage reactors is replenished by theaddition of make-up hydrogen.

The liquid stream separated from the gas stream is distilled to yieldthe required jet and diesel fuel in addition to other light liquid andgases which are disposed of or used as in any conventional refinery. Thelight liquid products can be light paraffins that result from mildhydrocracking that occurs in the second-stage reactor.

The process produces hydrocarbon liquid to meet all the requiredspecifications of diesel and aviation fuels. The yield of jet and dieselproduct per unit feed oil is maximized with lower production of lighterhydrocarbons in the process. With less light hydrocarbons and less watermade in the process, the overall hydrogen make-up requirement will beless. Hydrogen is a reactant in the process to convert bio-feedstocks tospecification biofuels. Hydrogen consumption levels have significantimpact on the economics of the overall process.

The recycle hydrogen gas from the first stage can be operated inonce-through mode. The once-through recycle hydrogen gas will containlarge amounts of CO and hydrogen besides CO₂ and other light hydrocarbonproduct gases. This gas mixture can be a good source for hydrogengeneration or to produce the needed process heat. Optionally, the unitcan be operated in recycle gas mode by continuously removing CO, CO₂,and some light gases from a separation unit downstream of thethree-phase separator. The CO and the light gases can be used to producethe necessary hydrogen for the process through steam reforming and watergas shift reactions.

Also, other bio-feedstocks like cellulose (wood chips, corn stover, farmresidues, etc.) can be used to produce hydrogen. These bio-feedstocksare steam reformed in a separate unit to produce hydrogen. Steamreforming (gasification) produces production gas which consists ofmostly hydrogen and oxides of carbon besides many contaminants. The gashas to be cleaned before it can undergo water-gas shift reaction toproduce hydrogen which can then be used in the process to convert cropoils and other bio-oils to specification biofuels.

One or more embodiments of the present invention comprise using at leastone crop oil such as, but not limited to, algae or microbial oil, canolaoil, corn oil, jatropha oil, camelina oil, rapeseed oil, pall oil, andcombinations thereof.

One or more embodiments of the present invention further include theoptions of co-feeding or mixing with a component derived from fossilfuels, depolymerization of waste plastics, thermal, chemical, orcatalytic, or synthetic oils derived from petrochemical or chemicalprocesses.

One or more embodiments of the present invention further includegenerating a gas stream that can be used to generate the process heatnecessary in a substantially high-temperature conversion process. Thisembodiment further improves the process economics.

Example 7 Jet/Aviation Fuel Synthesis from Bio-Oils Using NanocoatedPalladium on Activated Carbon Deoxygenation Catalyst

Refined Camelina oil was the feedstock used in a deoxygenation reactoraccording to one or more embodiments of the present invention.Deoxygenation experiments were carried out in a continuous down-flowmultiphase packed bed. Eleven grams of 1.72 wt % nanocoated Pd onactivated carbon catalyst according to one or more embodiments of thepresent invention was loaded into a stainless steel reactor.

The reactor was 0.305 inches in internal diameter and 18 inches longwith pre-heat and post-heat zones. The reactor volume was 22 cubiccentimeters. Heat for the reactor was supplied by a three-zonecontrolled furnace with heat equalizing blocks. The Camelina oil feedrate into the reactor was 0.1 cc/min. Liquid and gaseous productsexiting the reactor were collected in a separator. Backpressureregulators maintained the operating system pressure at 1000 psig.

The catalyst was reduced under hydrogen at 250° C. for 2 hours first.Reactor temperature was raised from 250° C. to 360° C. within 60minutes. Liquid Camelina oil was pumped into the reactor at a rate of0.1 cc/min. Hydrogen gas feed rate into the reactor was 135 cc/min.Reactor temperature was maintained at 360° C. and the reactor was runfor 24 hours. Reactor gas product was analyzed using a GC. The majorreactant gaseous product observed other than H₂ was CO. Paraffinic waxproduct was collected and separated from water by gravity.

Paraffinic wax from the deoxygenation reactor was fed to anisomerization/cracking reactor. The isomerization and hydrocrackingreactor used a commercially available standard catalyst. The paraffinicwax feed line was maintained at 40° C. to ensure that wax was properlypumped into the isomerization/cracking reactor. Theisomerization/cracking experiment was carried out in a continuousdown-flow multiphase packed bed reactor. Commercially availableisomerization catalyst totaling 3.8 grams was loaded into the stainlesssteel reactor.

The reactor was a 0.305 inch internal diameter and 5 inch long reactorwith pre-heat and post-heat zones. The reactor volume was 6 cc. Heat forthe reactor was supplied by a three-zone controlled furnace with heatequalizing blocks. A pump was used to pump the paraffinic wax feed at0.1 cc/min rate into the reactor. Liquid and gaseous products exitingthe reactor were collected in a separator. Backpressure regulatorsmaintained operating system pressure at 1000 psig. Theisomerization/cracking catalyst was reduced under hydrogen at 260° C.for 2 hours first. Reactor temperature was lowered to 232° C. Liquidparaffinic feed was then pumped into the reactor at a 0.1 cc/min rate.Hydrogen gas feed rate into the reactor was 83 cc/min. Reactortemperature was raised to and maintained at 360° C. and the reactor wasrun for 20 hours. The whole liquid product was collected from thereactor and analyzed using simulated distillation D-2887. The simulateddistillation analysis showed 80% by volume of jet fuel in the boilingrange of 244 F-597 F was produced.

Example 8 Diesel Fuel Synthesis from Bio-Oils Using Nanocoated Palladiumon Activated Carbon Deoxygenation Catalyst

Refined Camelina oil was the feedstock used in a deoxygenation reactoraccording to one or more embodiments of the present invention.Deoxygenation experiments were carried out in a continuous down-flowmultiphase packed bed reactor. Eleven grams of 1.72 wt % nanocoated Pdon activated carbon catalyst according to one or more embodiments of thepresent invention was loaded into a stainless steel reactor. The reactorwas a 0.305 inch internal diameter and 18 inch long reactor withpre-heat and post-heat zones. The reactor volume was 22 cc. Heat for thereactor was supplied by a three-zone controlled furnace with heatequalizing blocks. A pump was used to pump the Camelina oil feed at 0.1cc/min into the reactor. Liquid and gaseous products exiting the reactorwere collected in a separator. Backpressure regulators maintainedoperating system pressure at 1000 psig.

The catalyst was reduced under hydrogen at 250° C. for 2 hours. Reactortemperature was raised from 250° C. to 360° C. within 60 minutes. LiquidCamelina oil was pumped into the reactor at a 0.1 cc/min rate. Hydrogengas feed rate into the reactor was 135 cc/min. Reactor temperature wasmaintained at 360° C. and the reactor was run for 24 hours. Reactor gasproduct was analyzed using a GC. The major reactant gaseous productobserved other than H₂ was CO. Paraffinic wax product was collected andseparated from water by gravity.

Paraffinic wax from the deoxygenation reactor was fed to anisomerization/cracking reactor. The paraffinic wax feed line wasmaintained at 40° C. to ensure that wax was properly pumped into theisomerization/cracking reactor. The isomerization/cracking experimentwas carried out in a continuous down-flow multiphase packed bed reactor.Commercially available isomerization catalyst totaling 3.8 grams wasloaded into the stainless steel reactor.

The reactor was 0.305 inches in internal diameter and 5 inches long withpre-heat and post-heat zones. The reactor volume was 6 cc. Heat for thereactor was supplied by a three-zone controlled furnace with heatequalizing blocks. A pump was used to pump the paraffinic wax feed at0.1 cc/min into the reactor. Liquid and gaseous products exiting thereactor were collected in a separator. Backpressure regulatorsmaintained operating system pressure at 1000 psig. Theisomerization/cracking catalyst was reduced under hydrogen at 260° C.for 2 hours. Reactor temperature was lowered to 232° C. Liquidparaffinic feed was then pumped into the reactor at a 0.1 cc/min rate.Hydrogen gas feed rate into the reactor was 83 cc/min. Reactortemperature was raised to and maintained at 325° C. and the reactor wasrun for 20 hours. The whole liquid product was collected from thereactor and analyzed using simulated distillation D-2887. The simulateddistillation analysis showed 84% by volume of diesel fuel in the boilingrange of 504 F-765 F was produced.

Methods according to one or more embodiments of the present inventionmay also comprise depositing palladium to make palladium membranes forhydrogen separation. Methods according to one or more embodiments of thepresent invention may also comprise depositing palladium and/or othermetals nanoscale coatings on zeolites, alumina, or silica-aluminasubstrates to make catalyst for hydrocracking applications ofhydrocarbon fuels.

In the foregoing specification, the invention has been described withreference to specific embodiments; however, one of ordinary skill in theart appreciates that various modifications and changes can be madewithout departing from the scope of the present invention as set forthin the claims below. Accordingly, the specification is to be regarded inan illustrative rather than a restrictive sense, and all suchmodifications are intended to be included within the scope of thepresent invention.

Benefits, other advantages, and solutions to problems have beendescribed above with regard to specific embodiments; however, thebenefits, advantages, solutions to problems, and any element(s) that maycause any benefit, advantage, or solution to occur or become morepronounced are not to be construed as a critical, required, or essentialfeature or element of any or all the claims.

As used herein, the terms “comprises,” “comprising,” “includes,”“including,” “has,” “having,” “at least one of,” or any other variationthereof, are intended to cover a non-exclusive inclusion. For example, aprocess, method, article, or apparatus that comprises a list of elementsis not necessarily limited only to those elements, but may include otherelements not expressly listed or inherent to such process, method,article, or apparatus. Further, unless expressly stated to the contrary,“or” refers to an inclusive or and not to an exclusive or. For example,a condition A or B is satisfied by any one of the following: A is true(or present) and B is false (or not present), A is false (or notpresent) and B is true (or present), and both A and B are true (orpresent).

1-40. (canceled)
 41. A method of deoxygenating oxygenated hydrocarbons,the method comprising: providing a catalyst comprising a poroussubstrate and an electrolessly deposited catalytically effectivenanoscale metal coating on the substrate; contacting the catalyst withthe oxygenated hydrocarbons and hydrogen so as to accomplishhydrogenation and deoxygenation wherein the deoxygenation isaccomplished preferentially by decarbonylation and decarboxylation overhydrodeoxygenation.
 42. The method of claim 41, wherein the ratio ofdecarbonylation to decarboxylation is about 6:1.
 43. The method of claim41, wherein the metal comprises palladium.
 44. The method of claim 41,wherein the metal comprises nickel.
 45. The method claim 41, wherein themetal comprises chromium, molybdenum, tungsten, iron, ruthenium, osmium,cobalt, rhodium, iridium, platinum, zinc, silver, gold, copper, ormixtures thereof.
 46. The method of claim 41, wherein the substrate isactivated carbon.
 47. The method of claim 41, wherein the poroussubstrate comprises carbon foam, alumina, silica-alumina, metal foam,silica, zeolites, titania, zirconia, magnesia, chromia, monoliths, orcombinations thereof.
 48. The method of claim 41, wherein the poroussubstrate is granular and comprises activated carbon, alumina,silica-alumina, silica, titania, zirconia, magnesia, chromia, zeolites,or combinations thereof.
 49. The method of claim 41, wherein thecatalyst is catalytically active for hydrogenation and preferentialdeoxygenation of triglycerides by decarbonylation and decarboxylationover hydrodeoxygenation.
 50. The method of claim 41, wherein thecatalyst is catalytically active for preferential deoxygenation ofalcohols, ethers, aldehydes, ketones, carboxylic acids, esters,phenolics, or mixtures thereof by decarbonylation and decarboxylationover hydrodeoxygenation.
 51. The method of claim 41, further comprisingmaintaining carbon monoxide partial pressure up to about 0.1 megapascals(15 psi) wherein the metal comprises palladium.
 52. The method of claim41, wherein deoxygenation of triglycerides is by decarbonylation anddecarboxylation over hydrodeoxygenation so that the ratio of odd to evencarbon number in the deoxygenated product is about 6:1.
 53. The methodof claim 41, wherein the hydrocarbons comprise triglycerides, the carbonsubstrate is activated carbon, the metal comprises palladium, and thecontacting the catalyst with the hydrocarbons and hydrogen so as topreferentially accomplish deoxygenation by decarbonylation anddecarboxylation over hydrodeoxygenation is accomplished at temperaturesin the range 300° C. to 400° C. and pressures in the range 1.5megapascals to 15 megapascals.
 54. The method of claim 41, wherein thehydrocarbons comprise triglycerides, the substrate comprises activatedcarbon, carbon foam, alumina, metal foam, silica-alumina, silica,zeolites, titania, zirconia, magnesia, chromia, monoliths, orcombinations thereof, the metal is selected from the group consisting ofchromium, molybdenum, tungsten, iron, ruthenium, osmium, cobalt, nickel,rhodium, iridium, palladium, platinum, zinc, gold, silver, copper, ormixtures thereof, and the contacting the catalyst with the hydrocarbonsand hydrogen so as to preferentially accomplish deoxygenation bydecarbonylation and decarboxylation over hydrodeoxygenation isaccomplished at temperatures in the range 300° C. to 400° C. andpressures in the range 1.5 megapascals to 15 megapascals.
 55. The methodof claim 41, wherein the catalyst has a metal loading of less than orequal to about 2% with deoxygenation efficiency greater than about 90%.56. The method of claim 41, wherein the catalyst has a metal loading ofless than or equal to about 1% with deoxygenation efficiency greaterthan about 90%.
 57. The method of claim 41, wherein the weight hourlyspace velocity is 0.2 to 2.5.